The present invention relates generally to a resilient bumper used for protecting loading docks and other structures subject to damaging impacts of a vehicle, for example a transport vehicle when positioning up against a loading dock or the like. More particularly, the present invention relates to a loading dock bumper construction which provides the operator of a vehicle with a visual signal to guide the vehicle along a pathway to a predetermined proper position. The construction provides for and further indicates excessive wearing away of material in the bumper and enables the removal and replacement of such material.
The use of rubber tires and also pieces of rubber tires put together and fashioned in different ways is known in the art of loading dock bumpers. The art of cutting tires into almost flat sections and stacking these sections together to create a flexible and/or resilient stack is also known in the art.
U.S. Pat. No. RE 24276 to Schuyler, issued Feb. 12, 1957, discloses a loading dock bumper consisting of a plurality of resilient rubber like strips arranged face-to-face in a stacked relationship, and these strips are secured together at the two ends of the stack by a pair of angle brackets such that the rubber strips are directly exposed to the vehicle.
U.S. Pat. No. 3,165,305 to Pfleger, issued Jul. 12, 1965, discloses a truck dock bumper constructed from a stack of flat, rectangular rubber units, the stack having a rectangular tie bar extending therethrough from end-to-end to prevent sagging of the bumper in its middle and an offsetting relationship in the location of the mounting angles at the opposite ends of the bumper permitting close end-to-end disposition of adjacent bumpers.
U.S. Pat. No. 3,353,812 to Miller, issued Nov. 21, 1967, discloses a bumper constructed from a plurality of stacked rubber strips mounted and supported for attachment on a marine dock, loading dock and the like, by means of supports at least one of which is loosely mounted on the bumper.
U.S. Pat. No. 5,094,905 to Murray, issued Mar. 10, 1992, discloses a dock bumper constructed of rubber fragments mixed with an adhesive and bonded together, the rubber fragments being produced by fragmenting at least one tire containing rubber and strands of reinforcing material used to reinforce the tire, wherein a sufficient quantity of adhesive is mixed with the rubber to create a free standing article having structural integrity said dock bumper formed under pressure in a mold having the desired shape for a time period sufficient for the adhesive to set.
Since bumpers of this sort receive repeated impacts from vehicles, with time, due to the friction, the bumper will deteriorate. All bumpers of this type heretofore available have had at least one serious defect. Bumpers in service for a while and prior to their removal and replacement when worn, would deteriorate to a level which would interfere with the cushioning (dampening) function of the bumper thereby damaging the loading dock and/or vehicle which is backing up against the bumper.
It is also frequently necessary to accurately position a vehicle, such as a truck, within close proximity to a door opening in a building wall to facilitate the loading or unloading of the vehicle. In this case, along with similar cases, an operator must accurately guide the vehicle along a pathway, bringing it to a defined position in relationship to surrounding stationary structures, enclosures, or spaces.
It is not uncommon for damage to occur to the vehicle and/or surrounding structures which may be obscured from the driver's line of sight during the positioning process. Moreover, the initial positioning of the vehicle may be unsatisfactory. If this is the case, the positioning operation may have to be repeated, thereby leading to the possibility that damage will occur during repositioning. Alternatively, if repositioning is not performed, other consequential problems, such as difficulty in loading and unloading cargo, frequently arise. These and other problems inherent in vehicular positioning operations are well recognized, and various devices and techniques have been envisioned or devised to overcome such problems.
In the past, a number of different vehicle positioning guides have been proposed, such as, for instance, Tucker U.S. Pat. No. 3,893,068, issued Jul. 1, 1975, which discloses a guide device for use in the backing up of a towed trailer into a parking space which includes a pair of light containing units each having a housing with a light source contained therein and batteries contained therein for powering the light source, with each having a port extending through the front thereof for directing light forwardly therefrom, and a port disposed in the sides thereof to direct light sideways from the unit, one unit being positioned on each side of the parking space into which the trailer is to be backed into such that the units are visible to the vehicle driver and thus acting as guides for backing the trailer into the parking space.
In addition, White U.S. Pat. No. 5,285,205, issued Feb. 8, 1994, which discloses a vehicle guidance and positioning system utilizing a laser, the emitted beam from which is directed over the path along which a vehicle is to be guided. The laser beam impinges on a target area located on the vehicle in such a manner that the impingement of the laser beam on the target is continuously observable by the vehicle's operator. The operator steers the vehicle so that the laser beam continuously impinges on the target area until the vehicle reaches a preselected position in a confined space.
The prior art solutions appear to be complex devices which are expensive to manufacture, install and maintain.
Furthermore, upon the loading and/or unloading of a truck at a loading dock, a commonly used fork-lift will ride into the truck to drop-off or pick-up a load. Frequently, damage may occur to the forks and tires of the forklifts from loading dock bumpers during loading and/or unloading. As well, during loading the extra weight of the load and the fork lift moving onto and out of the truck will cause the truck's bumper to get caught on the top of the loading dock bumper resulting in difficulties when moving away from the loading dock.
It is thus an object of the invention to provide a bumper, preferably a loading dock bumper, with a wear indicator providing a quantitative measure of the amount of resilient material remaining in connection with the safe and effective operation of the bumper and indicates when the resilient material of the bumper is dangerously worn and should be replaced.
It is yet another object of the invention to provide a bumper, preferably a loading dock bumper, that has a substantially long wear life.
It is yet another object of the invention to provide a bumper, preferably a loading dock bumper, with a chamfered edge for preventing damage to forklifts or the like during loading and/or unloading and preventing a vehicle from becoming stuck on a loading dock bumper and causing problems during disengagement from the loading dock.
It is yet another object of the invention to provide a bumper, preferably a loading dock bumper, with a mounting element for removably mounting the bumper to facilitate the removal and replacement of the bumper when worn.
It is yet another object of the invention to provide a bumper, preferably a loading dock bumper, with a vehicle guidance and positioning system to quickly and accurately aid an operator in the guidance of a vehicle, leading the vehicle to the desired position at the loading dock both at night and during the day without requiring the assistance or guidance of other individuals.
It is yet another object of the invention to provide a bumper, preferably a loading dock bumper, that is economical to produce.
It is yet another object of the invention to provide a bumper, preferably a loading dock bumper, which uses waste material in the production thereof.
Further and other objects of the invention will be apparent to a person skilled in the art reading the following: